Methods and apparatus for controlling interference to broadcast signaling in a peer to peer network

ABSTRACT

Methods and apparatus related to broadcasting data and interference management in a peer to peer wireless communications network are described. Scheduling of traffic air link resources is performed on a slot by slot basis in a decentralized manner. Wireless devices intending to broadcast traffic signals transmit broadcast request signals, sometimes alternatively referred to as broadcast indicator signals. A priority level is associated with each of the broadcast request signals. A receiver device intending to receive broadcast signals detects the broadcast request signals and makes an interference determination as to whether the higher priority broadcast traffic signal can be successfully recovered in the presence of lower priority broadcast traffic signals. If the determination is that the expected interference from the lower priority broadcast traffic is unacceptable, the receiver device generates and transmits an interference control signal communicating to the lower priority device a command or request not to broadcast.

RELATED APPLICATIONS

The present application claims the benefit of U.S. Provisional PatentApplication Ser. No. 60/948,968 filed on Jul. 10, 2007, titled “METHODSAND APPARATUS FOR SENDING BROADCAST/MULTICAST MESSAGES IN A PEER-TO-PEERNETWORK”, and assigned to the assignee hereof and which is herebyexpressly incorporated by reference in its entirety.

FIELD

Various embodiments relate to wireless communications, and moreparticularly, to methods and apparatus related to supporting broadcastcommunications in a peer to peer network.

BACKGROUND

In a wireless communications system there is typically a fixed amount ofair link resources available for utilization by wireless communicationsdevices for combined control signaling and traffic signaling. In awireless communications system lacking centralized control, e.g., an adhoc peer to peer network, the scheduling of traffic air link resourcesis a challenging task.

A first device in a peer to peer network may desire to broadcast data toa plurality of other devices in the network, e.g., an open ended set ofdevices, which may happen to be in its local vicinity at the time.Similarly, a second device in the peer to peer network may also desireto broadcast data to a plurality of other devices in the network whichmay happen to be in its local vicinity. Using a broadcast signalingapproach can, at times, be more efficient than having to schedule andtransmit the same unicast data signals to multiple devices over multiplepeer to peer connections. However, if both the first and second devicewere to broadcast at the same time using the same air link resource in apeer to peer network, recovery of the broadcast signal information bypossible receiver devices may be unacceptable depending upon devicelocations, transmission power levels, channel conditions, receivercapabilities, etc. Based on the above discussion, there is a need formethods and apparatus which support broadcast data signaling in a peerto peer network and provide for interference management.

SUMMARY

Methods and apparatus related to broadcasting data and/or interferencemanagement in a peer to peer wireless communications network aredescribed. In various embodiments scheduling of traffic air linkresources is performed on a slot by slot basis in a decentralizedmanner. Wireless devices intending to broadcast traffic signals transmitbroadcast request signals, sometimes alternatively referred to asbroadcast indicator signals. A priority level is associated with each ofthe broadcast request signals. A receiver device intending to receivebroadcast signals detects the broadcast request signals and makes aninterference determination as to whether the higher priority broadcasttraffic signal can be successfully recovered in the presence of lowerpriority broadcast traffic signals. If the determination is that theexpected interference from the lower priority broadcast traffic isunacceptable, the receiver device generates and transmits aninterference control signal. The interference control signal, expectedto be received by the lower priority device which intended to broadcast,communicates to the lower priority device that the receiver devicecommands or requests that the lower priority device not broadcast.

An exemplary broadcast transmission method in accordance with someembodiments comprises: transmitting a broadcast indicator signalindicating an intent to broadcast data; monitoring for interferencecontrol signals following transmission of said broadcast indicatorsignal; and making a decision whether or not to proceed withbroadcasting data based on the result of said monitoring. An exemplarywireless terminal in accordance with some embodiments comprises: abroadcast indicator signal generation module configured to generate abroadcast indicator signal indicating an intent to broadcast data; abroadcast indicator signal control module configured to control awireless transmitter module to broadcast said generated broadcastindicator signal; a response monitoring module configured to monitor forinterference control signals following transmission of said broadcastindicator signal; and a broadcast decision module configured to make adecision whether or not to proceed with broadcasting data based on theresult of said monitoring.

An exemplary method of operating a first device in accordance with someembodiments comprises: receiving, from a second device a first broadcastindicator signal having a first priority corresponding to said seconddevice, said first broadcast indicator signal indicating an intent bythe second device to broadcast data; receiving from a third device asecond broadcast indicator signal having a second priority correspondingto said third device, said second broadcast indicator signal indicatingan intent by the third device to broadcast data; and making a decisionas to whether or not to transmit an interference control signal as afunction of the relative priority of the first and second broadcastindicator signals. An exemplary wireless communications device, inaccordance with some embodiments, comprises: a wireless receiver moduleconfigure to receive signals; and a broadcast signal monitoring moduleconfigured to: (i) detect in said received signals a first broadcastindicator signal from a second device, said first broadcast indicatorsignal having a first priority corresponding to said second device, saidfirst broadcast indicator signal indicating an intent by the seconddevice to broadcast data; and (ii) detect in said received signals asecond broadcast indicator signal from a third device, said secondbroadcast indicator signal having a second priority corresponding tosaid third device, said second broadcast indicator signal indicating anintent by the third device to broadcast data. The exemplary wirelesscommunications device further comprises an interference controlsignaling decision module for making a decision as to whether or not totransmit an interference control signal as a function of the relativepriority of the first and second broadcast indicator signals.

While various embodiments have been discussed in the summary above, itshould be appreciated that not necessarily all embodiments include thesame features and some of the features described above are not necessarybut can be desirable in some embodiments. Numerous additional features,embodiments and benefits of various embodiments are discussed in thedetailed description which follows.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a drawing of an exemplary peer to peer network, e.g., anad-hoc communications network supporting broadcast traffic signaling, inaccordance with an exemplary embodiment.

FIG. 2 is a flowchart of an exemplary method of operating a firstdevice, e.g., a wireless communications device supporting broadcastsignaling and unicast signaling.

FIG. 3 is a drawing of an exemplary wireless terminal, e.g., a peer topeer mobile node supporting broadcast data signaling in accordance withan exemplary embodiment.

FIG. 4 is a flowchart of an exemplary method of operating acommunications device in accordance with an exemplary embodiment.

FIG. 5 is a drawing of an exemplary wireless terminal, e.g., a peer topeer mobile node supporting broadcast data signaling in accordance withan exemplary embodiment.

FIG. 6 is a flowchart of an exemplary method of operating a firstdevice, e.g., a wireless communications device implementing interferencecontrol for broadcast signaling.

FIG. 7 is a drawing of an exemplary wireless terminal, e.g., a peer topeer mobile node supporting interference management for broadcast datasignaling in accordance with an exemplary embodiment.

FIG. 8 is a drawing illustrating an exemplary recurring timing structurefacilitating broadcast and peer to peer unicast traffic signaling usedin some embodiments.

FIG. 9 illustrates exemplary broadcast transmission request air linkresources of FIG. 8 and exemplary broadcast receiver response air linkresources of FIG. 8 in more detail in accordance with one exemplaryembodiment.

FIG. 10 includes a drawing illustrating exemplary signaling in a regionof a peer to peer network which illustrates interference management ofbroadcast signaling in accordance with an exemplary embodiment.

FIG. 11 includes a drawing illustrating exemplary signaling in a regionof a peer to peer network which illustrates interference management ofbroadcast signaling in accordance with an exemplary embodiment.

DETAILED DESCRIPTION

FIG. 1 is a drawing of an exemplary peer to peer network 100, e.g., anad-hoc communications network, in accordance with an exemplaryembodiment. The exemplary network supports broadcast traffic signalingby peer to peer devices. The exemplary network supports broadcasttraffic signaling by peer to peer devices. Broadcasting includes, atleast in some embodiments, multicasting and can be open in terms of thenumber of devices which may receive the broadcast. Broadcast differsfrom what is sometimes called Groupcast in that in Groupcast thetransmission is to a closed group of users, e.g., where the number oflisteners is often known. In the case of broadcast, the broadcastingdevice may, but normally does not know, the number of listeners to thebroadcast.

Exemplary peer to peer network 100 includes a plurality of wirelessdevices (peer to peer broadcast capable communications device 1 102,peer to peer broadcast capable communications device 2 104, peer to peerbroadcast capable communications device 3 106, peer to peer broadcastcapable communications device 4 108, . . . , peer to peer broadcastcapable communications device N 110) supporting peer to peer trafficsignaling and broadcast traffic signaling. In some embodiments, thenetwork 100 includes a reference signal transmitter 116, e.g., a beacontransmitter. In some embodiments, reference signal transmitter oranother device in the network communicates network configuration controlinformation such as information identifying a mixture between slotsdesignated as broadcast/unicast traffic slots and slots designated asunicast slots.

The wireless devices (102, 104, 106, 108, . . . , 110) in thecommunications network 100 can establish connections with one another,e.g., peer to peer connections, transmit unicast peer to peer trafficsignals, and transmit broadcast traffic signals. There is a recurringtiming structure used in the network 100. In some embodiments areference signal, e.g., an OFDM beacon signal from reference signaltransmitter 116, is used by a wireless device to synchronize withrespect to the timing structure. Alternatively, a signal used tosynchronize with the timing structure may be sourced from anotherdevice, e.g., a GPS transmitter, a base station or another peer to peerdevice. The timing structure used in the network includes a plurality ofindividual traffic slots.

FIG. 2 is a flowchart 200 of an exemplary method of operating a firstdevice, e.g., a wireless communications device supporting broadcastsignaling and unicast signaling. Operation starts in step 202 where thefirst device is powered on and initialized. Operation proceeds fromstart step 202 to step 204 and step 210.

In step 204, which is performed on an ongoing basis, the first devicemonitors for data to be transmitted. Step 204 may, and sometimes doesinclude sub-step 206, in which the first device receives data to betransmitted, e.g., from a user I/O device. For received data to betransmitted, operation proceeds from step 204 to step 207 and step 208.In step 207 the first device stores the received data in a queue. Instep 208 the first device designates the received data to be transmittedas broadcast data or unicast data.

Returning to step 210, in step 210 the first device determines if thereis currently queued data waiting to be transmitted. If the determinationof step 210 is that there is queued data waiting to be transmitted, thenoperation proceeds from step 210 to step 212; otherwise, operationproceeds from the output of step 210 to the input of step 210 foranother test at a later point in time as to whether or not there isqueued data waiting to be transmitted.

Returning to step 212, in step 212 the first device determines whetherbroadcast data is to be transmitted or whether unicast data is totransmitted. Step 212 includes sub-steps 214 and 216. At times sub-step214 is performed in which the first device determines that broadcastdata is to be transmitted. In such a situation, operation proceeds fromsub-step 214 to step 218. At times, sub-step 216 is performed in whichthe first device determines that unicast data is to be transmitted. Insuch a situation, operation proceeds from sub-step 216 to step 226.

Returning to step 218, in step 218 the first device identifies abroadcast transmission request resource in a recurring timing structureincluding transmission request intervals of a first type which supportbroadcast transmission requests and a second time which are limited tosupporting unicast transmission requests. In some embodiments,transmission request intervals of the first type support both broadcastand unicast transmission requests. In some embodiments, the number ofsecond type request intervals exceeds the number of first type requestintervals.

In various embodiments, the recurring timing structure includes slotsdedicated to unicast transmissions and slots that support broadcasttransmissions. In some such embodiments, at least some of the slotswhich support broadcast transmissions also support unicasttransmissions. In some such embodiments, broadcast transmission requestresources corresponding to a slot which supports both unicast andbroadcast transmissions have a higher priority than unicast transmissionrequest resources corresponding to that slot.

Operation proceeds from step 218 to step 220. In step 220 the firstdevice transmits a transmission request in said identified broadcaststransmission request resource. In some embodiments, transmitting atransmission request said identified broadcast transmission requestresource includes transmitting in a slot which supports broadcasttransmissions. Operation proceeds from step 220 to step 222. In step 222the first device determines whether or not it received a transmissionrequest response, e.g., an interference control signal, in a higherpriority request response resource. If it has not received a higherpriority request response, then operation proceeds from step 222 to step224 where the first device transmits broadcast data; otherwise,operation proceeds from step 222 to connecting node A 234. Operationproceeds from step 224 to connecting node A 234.

Returning to step 226, in step 226 the first device identifies a unicasttransmission request resource in said recurring timing structure.Operation proceeds from step 226 to step 228, in which the first devicetransmits a transmission request in the identified unicast requestresource which is in a transmission slot. In some embodiments,transmitting a transmission request in said identified unicasttransmission request resource includes transmitting a request in atransmission slot which supports unicast transmissions. Operationproceeds from step 228 to step 230. In step 230 the first devicedetermines if it has received a request response in response to thetransmitted transmission request of step 228 and if it has decided notto yield. If the first device has received a request response and hasdecided not to yield, then operation proceeds from step 230 to step 232,where the first device transmits unicast data; otherwise, operationproceeds from step 230 to connecting node A 234. In some embodiments,traffic data transmission intervals in the recurring timing structurewhich are limited to unicast data transmission are limited tocorresponding transmission request intervals of the second type.

Operation proceeds from step 232 to connecting node A 234. Operationproceeds from connecting node A 234 to step 210, where the first devicechecks if there is any queued data is waiting to be transmitted.

In some embodiments, the exemplary method also includes steps 241 and243. In step 241, which in some embodiments is performed on an ongoingbasis, the first device monitors for system configuration informationsignals, e.g., at predetermined times in a recurring timing structure.Step 241 may, and sometimes does, includes sub-step 242 in which thefirst device receives configuration information, e.g., informationindicating a number of first type slots and second type slots in arecurring timing structure, information indicating a pattern of firsttype slots and second type slots in a recurring timing structure,information indicating a distribution of first type slots and secondtype slots in a recurring timing structure, and/or informationindicating one of a plurality of alternative recurring timingstructures. Operation proceeds from sub-step 242 to step 243, in whichthe first device implements and/or adjusts operations in accordance withthe received configuration information. In some embodiments,configuration information in a region of the network can be, andsometimes is, adjusted dynamically, e.g., in response to current networkconditions and/or needs. For example, the timing structure may bemodified to include more or less slots supporting broadcast traffic tosatisfy current conditions and/or needs. In some embodiments, theconfiguration information is communicated via a fixed locationtransmitter, e.g., a beacon transmitter.

FIG. 3 is a drawing of an exemplary wireless terminal 300, e.g., a peerto peer mobile node, supporting broadcast data signaling in accordancewith an exemplary embodiment. Exemplary wireless terminal 300 includes awireless receiver module 302, a wireless transmitter module 304, aprocessor 306, user I/O devices 308 and a memory 310 coupled togethervia a bus 312 over which the various elements CAN exchange data andinformation. In some embodiments, wireless terminal 300 also includes anetwork interface 307 coupled to bus 312. Network interface 307 allowsthe wireless terminal 300 to be coupled to a backhaul network, e.g., viaa wired or fiber optic link.

Memory 310 includes routines 318 and data/information 320. The processor306, e.g., a CPU, executes the routines 318 and uses thedata/information 320 in memory 310 to control the operation of thewireless terminal 300 and implement methods, e.g., the method offlowchart 200 of FIG. 2.

Wireless receiver module 302, e.g., an OFDM and/or CDMA receiver, iscoupled to receive antenna 314 via which the wireless terminal 300receives signals from other wireless devices. Received signals include,e.g., peer discovery signals, interference control signals communicatedon broadcast request response air link resources, unicast transmissionrequest response signals, channel quality information signals, andunicast traffic acknowledgment signals.

Wireless transmitter module 304, e.g., an OFDM and/or CDMA transmitter,is coupled to transmit antenna 316 via which the wireless terminal 300transmits signals to other wireless terminals. Transmitted signalsinclude, e.g., peer discovery signals, broadcast transmission requestsignals, unicast transmission request signals, pilot signals, broadcasttraffic signals and unicast traffic signals. In some embodiments, thesame antenna is used for receiver and transmitter.

Routines 318 include communications routine 322 and control routines324. The communications routine 322 implements the variouscommunications protocols used by the wireless terminal 300. Controlroutines 324 include a data monitoring module 326, a data storage module328, a transmission type classification module 330, a backlogdetermination module 332, a transmission type determination module 334,a broadcast resource identification module 340, a broadcast transmissionrequest signal generation module 342, a broadcast request control module344, a unicast resource identification module 346, a unicasttransmission request signal generation module 348, a unicast requestcontrol module 350, a broadcast response module 352, a unicast responsemodule 354, a broadcast traffic module 356 and a unicast traffic module358. Transmission type determination module 334 includes a broadcastdetermination module 336 and a unicast determination module 338. In someembodiments, control routines 324 includes configuration module 359.

Data/information 320 includes timing structure information 360,generated signals 397, received signals 398 and queued data andinformation 399. The generated signals 397 include, e.g., generatedbroadcast traffic transmission request signals, generated unicasttraffic transmission request signals, generated pilot signals fordetermining a unicast traffic rate, generated broadcast traffic signalsand generated unicast peer to peer traffic signals. The received signals398 include, e.g., received interference control signals, received peerto peer traffic transmission request response signals, received channelinformation signals, and received unicast traffic acknowledgmentsignals. The queued data and information 399 includes stored datawaiting to be transmitted via either broadcast traffic signals orunicast peer to peer traffic signals. The queued data and information399 also includes information classifying the type of transmissiontechnique to be used to transmit a portion, set, or block of storeddata, e.g., broadcast or unicast.

The timing structure information 360 includes recurring timing structureinformation 362. The recurring timing structure information 362 includespeer discovery interval information 364, broadcast/unicast slotinformation 366, unicast slot information 368 and slot type sequenceinformation 370. The broadcast/unicast slot information 366 includebroadcast pre-preamble resource information 372 unicast pre-preambleresource information 378, preamble resource information 384, dataresource information 386, and acknowledgment resource information 388.The broadcast pre-preamble resource information 372 includes broadcastrequest resource information 374 and broadcast response resourceinformation 376. The unicast pre-preamble resource information 378includes unicast request resource information 380 and unicast requestresponse resource information 382.

Unicast slot information 368 includes unicast high priority pre-preambleresource information 390, unicast low priority re-preamble resourceinformation 393, preamble resource information 393, data resourceinformation 395 and acknowledgment resource information 396. The unicasthigh priority pre-preamble resource information 390 includes unicastrequest resource information 391 and unicast request response resourceinformation 392. Similarly, the unicast low priority pre-preambleresource information 393 includes unicast request resource informationand unicast request response resource information.

Data monitoring module 326 monitors for data to be transmitted, e.g.,input data obtained via user I/O devices. Data monitoring module 326, attimes, receives data to be transmitted to other wireless devices. Datastorage module 328 stores received data to be transmitted, e.g., in atransmission queue as part of queued data and information 399.Transmission type classification module 330 classifies and/or designatesthe type of transmission to be used for the queued data to betransmitted, e.g., one of broadcast and unicast. The stored datatransmission type classification is stored along with the received datato be transmitted in queued data and information 399.

Backlog determination module 332 determines if there is currently queueddata waiting to be transmitted. Transmission type determination module334 determines whether broadcast data is to be transmitted or whetherunicast data is to be transmitted. Broadcast determination module 336determines if broadcast data is to be transmitted. Unicast determinationmodule 338 determines if unicast data is to be transmitted.

Broadcast resource identification module 340 identifies a broadcasttransmission request resource in a recurring timing structure includingtransmission request intervals of a first type which support broadcasttransmission requests and a second type which are limited to supportingunicast transmission requests. For example, the first type may includethe request resources of a broadcast/unicast slot, e.g. resourcesidentified by information 374 and information 380; the second type mayinclude the request resources of a unicast slot, e.g., resourcesidentified by information 391 and unicast request resource informationof information 393. As one example, broadcast resource identificationmodule identifies a transmission unit within broadcast request resourceinformation 374 associated with a broadcast device identifier currentlyheld by wireless terminal 300.

Broadcast transmission request signal generation module 342 generates abroadcast transmission request when the broadcast determination module336 determines that broadcast data is to be transmitted. Broadcastrequest control module 344 controls the wireless transmitter module 304to the transmit the generated broadcast transmission request in theidentified broadcast transmission request resource associated with thewireless terminal 300.

Unicast resource identification module 350 identifies a unicasttransmission request resource in a recurring timing structure includingtransmission request intervals of a first type which support broadcasttransmission requests and a second type which are limited to supportingunicast transmission requests. For example, unicast resourceidentification module 346 identifies a transmission unit within unicastrequest resource information 380, within unicast request resourceinformation 391, or within unicast request resource information ofinformation 393, associated with a connection identifier currently heldby wireless terminal 300 corresponding to the peer to peer connectionover which wireless terminal 300 desires to transmit the unicast trafficdata.

Unicast transmission request signal generation module 348 generates aunicast transmission request when the unicast determination module 338determines that unicast data is to be transmitted. Unicast requestcontrol module 350 controls the wireless transmitter module 304 totransmit the generated unicast transmission request in the identifiedunicast transmission request resource in a transmission slot whichsupports unicast transmissions.

Broadcast response module 352 monitors for, detects and measuresreceived interference control signals communicated on broadcasttransmission request resources, e.g., resources identified byinformation 376. Broadcast response module 352 makes a decision as towhether or not the wireless terminal 300 should proceed with an intendedbroadcast transmission or perform transmitter yielding and not transmitthe intended broadcast traffic signal. In some embodiments, thebroadcast response module 352 makes a decision to yield when it detectsa control interference signal corresponding to a higher priorityintended broadcast transmission above a threshold.

Unicast response module 354 monitors for detects, and measures receivedunicast transmission request response signals communicated on unicasttransmission request response resources. Unicast response module 354makes a decision whether or not wireless terminal 300 should proceedwith an intended unicast traffic transmission or should performtransmitter yielding. In some embodiments the unicast response modulemakes a decision to continue with the intended unicast transmission ifit detects a unicast request response signal corresponding to itspreviously transmitted unicast request response signal and does notdetect any unicast request response signals corresponding to higherpriority connections. If the unicast response module 354 detects aunicast request response corresponding its previously transmittedunicast transmission request and detects one or more unicasttransmission request responses corresponding to higher priorityconnections, then module 354 makes a transmitter yielding decision as afunction of the expected interference that it expects it will cause tothe other higher priority connections.

Broadcast traffic module 356 generates a broadcast traffic signal, whenthe broadcast response module 352 decides to proceed with the intendedbroadcast traffic transmission. Broadcast traffic module 356 controlsthe wireless transmitter module 304 to the transmit the generatedbroadcast traffic signal in the data resource, e.g., traffic segment,corresponding to the broadcast transmission request. For example, thetraffic segment used to carry the broadcast traffic signal may beidentified by data resource information 386 corresponding to a broadcasttransmission request conveyed in a broadcast transmission requestresource identified by information 374. In this exemplary embodiment,the broadcast traffic signal is transmitted at a predetermined datarate, e.g., a low data rate such that the broadcast traffic signal maybe expected to be recoverable under adverse channel conditions.

Unicast traffic module 358 generates a unicast traffic signal, when theunicast response module 354 decides to proceed with the intended unicasttraffic transmission. Unicast traffic module 358 controls the wirelesstransmitter module 304 to the transmit the generated unicast trafficsignal in the data resource, e.g., traffic segment, corresponding to theunicast transmission request which wireless terminal 300 previouslytransmitted. For example, if the unicast request was communicated usinga resource identified by information 380, a data resource, e.g., trafficsegment, identified by information 386 is used to carry the unicasttraffic signal. Alternatively, if the unicast request was communicatedusing a resource identified by information 391, a data resource, e.g.,traffic segment, identified by information 395 is used to carry theunicast traffic signal.

Unicast traffic module 358 also controls the data rate used for unicastdata transmission. The data rate used for unicast traffic may be, andsometimes does, vary from one slot to another, e.g., as a function ofchannel quality feedback information communicated in response to a pilotsignal. The pilot signal and the corresponding channel quality feedbackinformation are communicated using preamble resources, e.g., resourcesidentified by information 384 or information 394 depending upon theslot.

In this exemplary embodiments, unicast traffic acknowledgments arecommunicated in response to received unicast traffic signals. Unicasttraffic module 354 also monitors for and detects unicast trafficacknowledgments signals after it has transmitted unicast trafficsignals, e.g., using an acknowledgment resource identified byinformation 388 or information 396 depending upon the slot.

Wireless terminal 300 utilizes a recurring timing structure includingslots of a first type supporting both broadcast and unicast signalingand slots of a second type supporting unicast signaling but notbroadcast signaling. Thus a first type of slot, e.g., abroadcast/unicast slot such as that identified by information 366,includes requests interval resources to accommodate both broadcasttransmission requests and unicast transmission requests. A second typeof slot, e.g., a slot such as that identified by unicast slotinformation 368 include request interval resources accommodating unicasttraffic transmission request but no request resources accommodatingbroadcast traffic transmission requests. In this embodiment, the numberof the second type of slots exceeds the number of the first type ofslots in the recurring timing structure.

In this exemplary embodiment, transmission request intervals of a firsttype support both broadcast and unicast transmission requests. Thetransmission request interval for a broadcast/unicast slot identified byinformation 372 includes a number of consecutive transmission requestsub-intervals which may be non-contiguous, e.g., separated by responseintervals. For example, a first transmission request sub-interval maycorresponding to broadcast request resource information 374 and a secondsub-interval may correspond to unicast request resource information 382.

In this exemplary embodiment, the transmission request intervals of thesecond type are limited to supporting unicast transmission requests. Thetransmission request interval for a unicast slot identified byinformation 368 includes a number of consecutive transmission requestsub-intervals which may be non-contiguous, e.g., separated by responseintervals, which support unicast transmission requests but do notsupport broadcast transmission request.

The number of second type transmission requests intervals exceeds thenumber of first type transmission request intervals in the recurringtiming structure. Slot type sequence information 370 includesinformation identifying the sequence and number of broadcast/unicastslots and the sequence and number of unicast slots in the recurringtiming structure.

In this exemplary embodiment, data transmission intervals which arelimited to unicast data transmission are limited to correspondingtransmission request intervals of the second type. For example, a datatransmission interval identified by data resource information 395 islimited to corresponding transmission request intervals of the secondtype.

It may be observed that the recurring timing structure identified byinformation 362 includes slots dedicated to unicast transmission andslots that support broadcast transmissions. At least some of the slotswhich support broadcast transmissions also support unicasttransmissions, e.g., a slot identified by information 366 supports bothbroadcast and unicast transmissions.

In this exemplary embodiment, transmission request resourcescorresponding to broadcast transmissions in a slot which supports bothunicast and broadest transmission have a higher priority thantransmission request resources corresponding to unicast transmission forthe same slot. For example, resources identified by broadcast resourceinformation 374 have higher priority than resources identified byunicast request resource information 382.

Configuration module 359 detects configuration signals, e.g., from abeacon transmitter or other device communicating system information, andimplements a configuration in accordance with the information conveyedby the received configuration signals. In one embodiment, aconfiguration signal communications information used to set up and/orchange the mixture between the number of slots designated tobroadcast/unicast slots and the number of slots designated to be unicastslots in the recurring timing system being utilized in the vicinity.

FIG. 4 is a flowchart 400 of an exemplary method of operating acommunications device, e.g., a peer to peer wireless terminal supportingbroadcast signaling. The exemplary method starts in step 402, where thecommunications device is powered on and initialized. Operation proceedsfrom start step 402 to step 404. In step 404, the communications devicedetermines a priority level for a broadcast indicator signal. In someembodiments step 404 includes one or more of sub-steps 406 and 408. Insub-step 406 the communications device determines the priority levelbased on a time varying function. In sub-step 408 the communicationsdevice determines the priority level based on an identifiercorresponding to the communications device. Operation proceeds from step404 to step 410.

In step 410 the communications device transmits the broadcast indicatorsignal indicating an intent to broadcast data. In some embodiments, thebroadcast indicator signal is transmitted on a single tone of an OFDMsymbol. Operation proceeds from step 410 to step 412. In step 412 thecommunications device monitors for interference control signals.Operation proceeds from step 412 to step 414. In step 414 thecommunications device makes a decision whether or not to proceed withbroadcasting data based on the result of the monitoring of step 412.

In some embodiments, the broadcast indicator signal is transmitted at adetermined priority level and individual interference control signalsdetected by the monitoring each have a priority level, and making adecision whether or not to proceed with broadcasting includesdetermining if an interference control signal having a higher prioritythan the priority level of the transmitted broadcast indicator signalwas received. In some such embodiments, making a decision whether or notto proceed with broadcasting includes, when an interference controlsignal having a higher priority than the priority of the transmittedbroadcast indicator signal was received, making an interferencedetermination based on the power level of at least one receivedinterference control signal having a higher priority than the prioritylevel of the transmitted broadcast indicator signal. In someembodiments, making a decision whether or not to proceed withbroadcasting includes deciding not to broadcast when the interferencedetermination determines that an interference level above a thresholdlevel will be caused to the device which transmitted the interferencecontrol signal having the higher priority than the priority level of thetransmitted broadcast indicator signal, if the broadcast proceeds.

Operation proceeds from step 414 to step 416. In step 416, if thedecision of step 414 is to proceed with the broadcast, then operationproceeds from step 416 to step 418, where the communications devicetransmits data in a traffic slot corresponding to the transmittedbroadcast indicator signal; otherwise, operation proceeds from step 416to connecting node A 420. Operation proceeds from step 418 to connectingnode A 420. Operation proceeds from connecting node A 420 to step 404.

Consider an example, where the communications device performs twoiterations of the flowchart. In a first iteration, a first broadcastindicator signal indicating an intent to broadcast data may betransmitted at a first priority level, while during a second iteration,a second broadcast signal indicating an intent to broadcast data may betransmitted at a second priority level which is different from the firstpriority level. In some embodiments, priority corresponding to a deviceidentifier is varied in accordance with a hopping pattern in a recurringtiming structure. This feature of variation of priority facilitatesbroadcast opportunities for different devices which may be in conflictdue to interference issues.

FIG. 5 is a drawing of an exemplary wireless terminal 500, e.g., a peerto peer mobile node 500 supporting broadcast data signaling inaccordance with an exemplary embodiment. Exemplary wireless terminal 500is, e.g., one of the communications devices of FIG. 1. Exemplarywireless terminal 500 includes a wireless receiver module 502, awireless transmitter module 504, a processor 506, user I/O devices 508and a memory 510 coupled together via a bus 512 over which the variouselements may exchange data and information. In some embodiments,wireless terminal 500 also includes a network interface 507 coupled tobus 512. Network interface 507 allows the wireless terminal 500 to becoupled to a backhaul network, e.g., via a wired or fiber optic link.

Memory 510 includes routines 518 and data/information 520. The processor506, e.g., a CPU, executes the routines 518 and uses thedata/information 520 in memory 510 to control the operation of thewireless terminal 500 and implement methods, e.g., the method offlowchart 400 of FIG. 4.

Wireless receiver module 502, e.g., an OFDM and/or CDMA receiver, iscoupled to receive antenna 514 via which the wireless terminal 500receives signals from other wireless devices. Received signals includecontrol interference signals.

Wireless transmitter module 504, e.g., an OFDM and/or CDMA transmitter,is coupled to transmit antenna 516 via which the wireless terminal 500transmits signals to other wireless terminals. Transmitted signalsinclude broadcast indicator signals and broadcast traffic signals. Insome embodiments, the same antenna is used for receiver and transmitter.

Routines 518 include communications routine 522 and control routines524. The communications routine 522 implements the variouscommunications protocols used by the wireless terminal 500. Controlroutines 524 include a broadcast indicator signal generation module 526,a broadcast indicator signal control module 528, a response monitoringmodule 530, a broadcast decision module 532, a priority comparisonmodule 534, a power measurement module 536, an interferencedetermination module 538, a broadcast control module 540, a broadcastindicator signal priority level determination module 542, a broadcasttraffic signal generation module 544, and a broadcast traffic signalingcontrol module 546.

Data/information 520 includes recurring timing structure information548, a generated broadcast indicator signal 549, information identifyinga currently held broadcast device identifier 550, current timeinformation 552, determined priority level information 554, detectedinterference control signals' information 556, identified controlinterference signal(s) having higher priority than the priority of thegenerated transmitted broadcast indicator signal 558, broadcast decision560 and generated broadcast traffic signals 562. Detected interferencecontrol signals information 556 may, and sometimes does, includeinformation corresponding to one or more detected interference controlsignals ((detected control interference signal 1 564, received powerlevel information for detected control interference signal 1 566,priority level information associated with detected interference controlsignal 1 568), . . . , (detected control interference signal N 570,received power level information for detected control interferencesignal N 572, priority level information associated with detectedinterference control signal N 574)).

Broadcast indicator signal generation module 526 generates a broadcastindicator signal indicating an intent to broadcast data, e.g., signal549. Broadcast indicator signal control module 528 controls the wirelesstransmitter module 504 to broadcast a generated broadcast indicatorsignal. In some embodiments, the broadcast indicator signal istransmitted on a single tone of an OFDM symbol.

Response monitoring module 530 monitors for interference control signalsfollowing transmission of a broadcast indicator signal. Broadcastdecision module 532 makes a decision whether or not to proceed withbroadcasting data based on the result of the monitoring. In someembodiments, an interference control signal from another wirelessterminal is communicated on single tone of an OFDM symbol. In someembodiments, an interference control signal is a command from anotherwireless terminal not to broadcast data. In some embodiments, aninterference control signal is a request from another wireless terminalnot to broadcast data.

In some embodiments, the broadcast indicator signal is transmitted at afirst priority level and individual interference control signalsdetected by the monitoring each have a priority level. In some suchembodiments, priority level is associated with position of an air linkresource used to carry the signal of interest, e.g., the broadcastindicator signal and/or the interference control signal, in atiming/frequency structure. Broadcast indicator signal priority leveldetermination module 542 determines a priority level associated with abroadcast indicator signal to be transmitted by the wireless terminalbased on a time varying function and/or based on an identifiercorresponding to the wireless terminal. For example, wireless terminal500 may currently hold a device identifier associated with broadcasttransmission request air link resources and broadcast request responseair link resources. In addition, a recurring timing structure in use,and known to wireless terminal 500, may implement a hopping sequencesuch that a particular device identifier to be used for broadcast hasdifferent priority levels from one slot to another in the timingstructure.

Priority comparison module 534 determines if an interference controlsignal having a higher priority than the first priority was received,the first priority being the priority level associated with thebroadcast indicator signal transmitted by wireless terminal 500.Broadcast decision module 532 makes a decision whether or not to proceedwith broadcasting data as a function of the priority comparison module534 determination.

Power measurement module 536 measures the power level of receivedinterference control signals. Broadcast decision module 532 makes adecision whether or not to proceed with broadcasting data based on thepower level of at least one received interference control signal havinga higher priority than the first priority level when an interferencecontrol signal having a first priority level was detected by theresponse monitoring module 530.

Interference determination module 538 determines interference to otherdevices if the wireless terminal 500 should proceed with broadcastingdata. Broadcast decision module 532 makes a decision not to broadcastdata when the interference determination module 538 determines that aninterference level above a threshold will be caused to the device whichtransmitted the interference control signal having a higher prioritythan the first priority level if the broadcast proceeds.

Broadcast traffic signal generation module 544 generates broadcasttraffic signals, e.g., generated broadcast traffic signals 562. In someembodiments, the data rate of the broadcast traffic signals is fixed forwireless terminal 500, whereas if wireless terminal 500 were instead totransmit unicast peer to peer traffic signals using the same trafficdata air link resource, e.g., traffic segment, the data rate of such agenerated peer to peer unicast traffic signals could be one a pluralityof different alternative data rates. In some embodiments, the transmitpower level of the broadcast traffic signals is fixed for wirelessterminal 500, whereas if wireless terminal 500 were instead to transmitunicast peer to peer traffic signals using the same traffic data airlink resource, e.g., traffic segment, the power level of such agenerated peer to peer unicast traffic signals could be one a pluralityof different alternative power levels.

Broadcast traffic signaling control module 546 controls the wirelesstransmitter module 504 to broadcast data in a traffic slot correspondingto a transmitted broadcast indicator signal when the decision by thebroadcast decision module 532 is a decision to broadcast data.

FIG. 6 is a flowchart 600 of an exemplary method of operating a firstdevice, e.g., a wireless communications device supporting interferencecontrol for broadcast signaling. Operation of the exemplary methodstarts in step 602, where the communications device is powered on andinitialized. Operation proceeds from step 602 to step 604.

In step 604 the first device receives from a second device a firstbroadcast indicator signal having a first priority corresponding to thesecond device, said first broadcast indicator signal indicating anintent by the second device to broadcast data. Operation proceeds fromstep 604 to step 606, in which the first device receives from the thirddevice a second broadcast indicator signal having a second prioritycorresponding to the third device, said second broadcast indicatorsignal indicating an intent by the third device to broadcast data. Insome embodiments, steps 604 and 606 may be, and sometimes are, performedin parallel, e.g., with both the first and second broadcast indicatorsignals being received by the first device within the same OFDM symboltransmission time interval. Operation proceeds from step 606 to step608.

In step 608 the first device makes a decision whether or not to transmitan interference control signal as a function of the relative priority ofthe first and second broadcast indicator signals. Step 608 includessub-steps 610, 612, 614 and 616. In sub-step 610 the first devicedetermines if broadcasting data by the lower priority one of the secondand third device will produce an unacceptable level of interference tothe higher priority one of the second and third devices. In sub-step 612if the determination of sub-step 610 is that the broadcasting by thelower priority one other second and third devices will produce anunacceptable level of interference, then operation proceeds fromsub-step 612 to sub-step 614; otherwise, operation proceeds fromsub-step 612 to sub-step 616.

Returning to sub-step 614, in sub-step 614 the first device decides totransmit an interference control signal. Operation proceeds fromsub-step 614 to step 618. Returning to sub-step 616, in sub-step 616,the first device decides not to transmit an interference control signal.Operation proceeds from sub-step 616 to connecting node A 624.

Returning to step 618, in step 618 the first device transmits aninterference control signal. In some embodiments, step 618 includessub-steps 620 and 622. In sub-step 620 the first device selects andinterference signal resource from a plurality of interference signaltransmission resources having a priority level of the higher one of thesecond and third devices. Then in sub-step 622 the first devicetransmits the interference control signal at the priority level of thehigher priority one of the second and third devices. Operation proceedsfrom step 618 to connecting node A 624. Operation proceeds fromconnecting node A 624 to step 604.

In some embodiments, the interference signal transmission resources areindividual OFDM tone-symbols. In some embodiment the priorities of thesecond and third devices changes with time, e.g., from one slot toanother.

FIG. 7 is a drawing of an exemplary wireless terminal 700, e.g., a peerto peer mobile node 700 supporting interference management for broadcastdata signaling in accordance with an exemplary embodiment. Exemplarywireless terminal 700 is, e.g., one of the communications devices ofFIG. 1. Exemplary wireless terminal 700 includes a wireless receivermodule 702, a wireless transmitter module 704, a processor 706, user I/Odevices 708 and a memory 710 coupled together via a bus 712 over whichthe various elements may exchange data and information. In someembodiments, wireless terminal 700 also includes a network interface 707coupled to bus 712. Network interface 707 allows the wireless terminal700 to be coupled to a backhaul network, e.g., via a wired or fiberoptic link.

Memory 710 includes routines 718 and data/information 720. The processor706, e.g., a CPU, executes the routines 718 and uses thedata/information 720 in memory 710 to control the operation of thewireless terminal 700 and implement methods, e.g., the method offlowchart 600 of FIG. 6.

Wireless receiver module 702, e.g., an OFDM and/or CDMA receiver, iscoupled to receive antenna 714 via which the wireless terminal 700receives signals from other wireless devices. Received signals includecontrol broadcast indicator signals and broadcast traffic signals.

Wireless transmitter module 704, e.g., an OFDM and/or CDMA transmitter,is coupled to transmit antenna 716 via which the wireless terminal 700transmits signals to other wireless terminals. Transmitted signalsinclude interference control signals. In some embodiments, the sameantenna is used for receiver and transmitter.

Routines 718 include communications routine 722 and control routines724. The communications routine 722 implements the variouscommunications protocols used by the wireless terminal 700. Controlroutines 724 include a broadcast indicator signal monitoring module 726,an interference control signaling decision module 728, an interferencecontrol signal generation module 732, an interference control signalcontrol module 734, and a broadcast traffic signal recovery module 738.Interference control signaling decision module 728 includes aninterference tolerance determination sub-module 730. Interferencecontrol signal control module 734 includes a response resource selectionmodule 736.

Data/information 720 includes recurring timing structure information740, detected broadcast indicator signals' information 744, informationidentifying the identified highest priority detected broadcast indicatorsignal 758, determined estimated interference 760, an interferencetolerance threshold 762, an interference control signal transmissiondecision 764, a generated interference control signal 766, informationidentifying a set of response resources associated with the highestpriority detected broadcast signal 768, a selected response transmissionunit 770, and received broadcast traffic signals data/information 772.The detected broadcast signals' information 744 includes informationcorresponding to a plurality of detected broadcast indicator signalscorresponding to the same data transmission slot ((detected broadcastsignal 1 746, received power level information of detected broadcastsignal 1 748, priority level information associated with detectedbroadcast indicator signal 1 750), (detected broadcast signal 2 752,received power level information of detected broadcast signal 2 754,priority level information associated with detected broadcast indicatorsignal 2 756)).

Broadcast indicator signal monitoring module 726 detects broadcastindicator signals from received signals. Broadcast indicator signalmonitoring module 726 is configured to: (i) detect in received signals afirst broadcast indicator signal from a second device, said firstbroadcast indicator signal having a first priority corresponding to thesecond device, said first broadcast indicator signal indicating anintent by the second device to broadcast data; and (ii) detect inreceived signals a second broadcast indicator signal from a thirddevice, said second broadcast indicator signal having a second prioritycorresponding to the third device, said second broadcast indicatorsignal indicating an intent by the third device to broadcast data. Forexample, in the same slot in a recurring timing structure in use, both asecond and third device may intend to transmit broadcast traffic signalsusing the same air link data resource, e.g., the same traffic segment,and each may have transmitted a broadcast indicator signal which wasreceived and detected by the broadcast indicator signal monitoringmodule 726 and different priorities may be associated with the twodifferent detected broadcast indicator signals.

Interference control signaling decision module 728 makes a decisionwhether or not to transmit an interference control signal as a functionof the relative priority of first and second received detected broadcastindicator signals. Interference tolerance determination sub-module 730determines if a broadcast by the lower priority one of the second andthird devices will produce an unacceptable level of interference to thehigher priority one of the second and third devices. In other words,interference tolerance determination sub-module 730 determines ifallowing the lower priority device to broadcast data concurrently withthe higher priority device is expected to unacceptably impact thesuccessful recovery by wireless terminal 700 of the broadcast data fromthe higher priority device.

Interference control signal generation module 732 generates aninterference control signal, e.g., signal 766. In some embodiments, theinterference control signal is a signal instructing at least one lowerpriority device which intends to broadcast to refrain from broadcasting.In some embodiments, the interference control signal is a signalrequesting at least one lower priority device which intends to broadcastto refrain from broadcasting. In various embodiments, the interferencecontrol signal is a signal communicated using a single tone of an OFDMsymbol.

Interference control signal control module 734 controls the wirelesstransmitter module 704 to transmit a generated control interferencesignal when the interference control signaling decision module 728decides to transmit an interference control signal. Interference controlsignaling decision module 728 decides to transmit an interferencecontrol signal when the interference tolerance determination sub-module730 determines that the level of interference is unacceptable. Theinterference control signal control module 734 is configured to controlthe wireless transmitter module 704 to transmit a generated interferencecontrol signal at a priority level corresponding to the priority levelof the higher priority one of the second and third devices, the secondand third devices being the two devices from which broadcast indicatorsignals were detected and used for the interference tolerancedetermination.

Response resource selection module 736 selects an interference signalingair link resource from a plurality of interference signal transmissionresources having the priority level of the higher one of the second andthird devices. For example, for a given slot in the recurring structure,corresponding to each broadcast device identifier there is (i) a singlebroadcast transmission request resource designated to carry a broadcastindicator signal and (ii) a corresponding plurality of broadcasttransmission request response resources each of which may be used tocarry a interference control signal, and response resource selectionmodule 736 makes a selection of which one of the plurality of broadcasttransmission request response resources corresponding to the higherpriority device to use to send the control interference signal. In someembodiments, response resource selection module 736 makes its selectionpseudo-randomly. In some embodiments, the interference signaltransmission resources are individual OFDM tone-symbols, where an OFDMtone-symbol is one ODFM tone for the duration of one OFDM symboltransmission time interval.

Broadcast traffic signal recovery module 738 recovers broadcast datasignals and information communicated in a traffic segment, e.g.,broadcast signals corresponding to the highest priority broadcastindicator signal which was detected for the slot. Note the recovery maybe, and sometimes is, facilitated by transmitter yielding performed byone or more of the lower priority devices which had intended tobroadcast during the same slot but which yielded in response to aninterference control signal from wireless terminal 700.

Recurring timing structure information 740 includes informationidentifying a plurality of slots supporting broadcast transmissioncapability, and information identifying air link resources within thoseslots. Air link resources for an individual slot include air linkresources designated to carry broadcast indicator signals, e.g.,broadcast request resources, air link resources designated to carryinterference control signals, e.g., broadcast request responseresources, and resources designated to carry traffic signals which mayinclude broadcast traffic signals, e.g., a traffic segment. DeviceID/priority/index information 742 includes information which associatesa particular broadcast device identifier with a particular priority foreach of a plurality of slots in the recurring structure. The prioritylevel associated with a particular broadcast device identifier can be,and sometimes is, different for at least some different slots, e.g., inaccordance with a hopping sequence. In some embodiments, priority isassociated with position in a resource block, e.g., position of atransmission unit in a broadcast transmission request block and/orposition of a transmission unit or set of transmission units in abroadcast transmission request response block. By varying the priorityassociated with a broadcast device identifier over the recurring timingstructure, different devices are afforded the opportunity to be allowedto broadcast where interference occurs, e.g., the same device is notcontinually blocked via control interference signals.

Detected broadcast indicator signals information 744 representsinformation corresponding to signals detected by broadcast indicatormonitoring module 726. Identified highest priority detected broadcastindicator signal 758 includes information identifying one of the signalsin information 744. Determined estimated interference 760 is a result ofprocessing by interference tolerance determination sub-module 730.Interference tolerance threshold information 762 is a limit value, e.g.,a predetermined stored value, used by interference tolerancedetermination sub-module 730, along with determined estimateinterference 760 in making a determination. Interference control signaltransmission decision 764 is an output of interference control signalingdecision module 728 and used an input by interference control signalcontrol module 734. Information identifying a set of response resourcesassociated with a highest priority detected broadcast indicator signal768 is an input of response resource selection module 736, whileselected response transmission unit 770 is an output of module 736.Received broadcast traffic signals data/information 772 is an output ofbroadcast traffic signal recovery module 738.

It should be appreciated that, corresponding to a single broadcastindicator signal associated with a high priority broadcast deviceidentifier, multiple receiver devices may, and sometimes do, decide thatallowing a lower priority data broadcast data concurrently with abroadcast from that high priority device is unacceptable in terms ofbeing able to recover the higher priority data broadcast. In such asituation, the multiple receiver devices, of which device 700 may beone, may each send out a control interference signal. By each receiverdevice selecting pseudo-randomly one transmission unit from a pluralityof transmission units associated with the higher priority device forwhich to send its control interference signal, the likelihood ofcollision between two control interference signals is reduced. Acollision with construction interference could result in unintendedbroadcasting devices deciding to refrain from transmitting. A collisionwith destructive interference could result in a device for which acontrol interference signal is intended failing to detect the signal andfailing to cancel its intended broadcast transmission.

FIG. 8 is a drawing 800 illustrating an exemplary recurring timingstructure used in some embodiments. The exemplary structure of FIG. 8may be using in any of the networks of devices described with respect toFIG. 1, 2, 3, 4, 5, 6, 7, 10 or 11. Drawing 800 illustrates time axis801 and a plurality of slots (peer discovery slot 802, broadcast/unicastslot 804, unicast slot 806, unicast slot 808, broadcast/unicast slot810, unicast slot 812, . . . , peer discovery slot 814, . . . ). Peerdiscovery slot 802 is used by wireless peer to peer devices tocommunicate device identifier signals with one another, establishconnections with one another, and/or obtain resources associated with aconnection and/or a broadcast opportunity. A broadcast/unicast slot,e.g., slot 804, is structured to support broadcast data trafficsignaling and unicast data traffic signaling, e.g., peer to peer unicastdata traffic signaling. A unicast slot, e.g., slot 806 is structured tosupport unicast data traffic signaling, e.g., peer to peer data trafficsignaling. In this exemplary embodiment, there are more unicast slotsthan there are broadcast/unicast slots for one iteration of therecurring timing structure. In some embodiments, the periodicity ofbroadcast enabled slots is controlled by a system parameter. In somesuch embodiments, the parameter can be changed dynamically duringoperation to adjust the balance between broadcast/unicast slots andunicast slots to accommodate current needs.

Exemplary broadcast unicast/slot 804 includes a broadcast pre-amble airlink resource portion 816, a unicast pre-amble air link resource portion818, a preamble air link resource portion 820, a data air link resourceportion 822, and an acknowledgment air link resource portion 824.Broadcast pre-amble 816 includes a broadcast transmission request airlink resource portion 826, a broadcast receiver response air linkresource portion 828, a unicast transmission request air link resourceportion 830, and a unicast receiver transmission request response airlink resource portion 832. In this example, broadcast transmissionrequests communicated in broadcast transmission request air link portion826 have higher priority than unicast transmission requests communicatedin unicast transmission request air link resource portion 830. Therequests, whether a broadcast request or a unicast request are requeststo use the corresponding data air link resource portion in the slot.

Broadcast signaling, if requested, takes precedence over unicastsignaling for broadcast/unicast slot 804. However, if there is nobroadcast traffic in a neighborhood, then the data air link resourceportion 822 can be, and sometimes is, used to carry peer to peer unicasttraffic signals.

Broadcast pre-amble 816 is used for scheduling of broadcast traffic tobe communicated in data resource 822. Unicast pre-amble 818 is used forscheduling of peer to peer traffic to be communicated in data resource822. Preamble 822 is used for rate scheduling of peer to peer traffic tobe communicated using data resource 822. Preamble 818 in someembodiments, includes resources allocated to pilot signals and resourcesallocated to channel quality information and/or data rate informationsignals. Data resource 822 is used to carry broadcast traffic signalsand/or peer to peer traffic signals. Acknowledgment resource 824 is usedto carry traffic acknowledgments for peer to peer traffic signals whencommunicated.

In some embodiments, the pre-amble resource 820 and/or theacknowledgment resource 824 are not used for broadcast signalingpurposes. In some embodiments, a broadcast channel is a single ratebroadcast channel, e.g., with data coded at a low predetermined rate,and thus the pre-amble portion is not needed nor used to determine andset a broadcast data rate. In some embodiments, a device which intendsto broadcast will send out a pilot for unicast receivers to receive andutilize in estimating interference damage. In some embodiments, such apilot is communicated in preamble 820, while in other embodiments such apilot may be communicated in another portion, e.g., a discovery signalfrom the broadcast device may be utilized.

Broadcast transmission request air link resource portion 826 is used tocarry broadcast requests, sometimes alternatively referred to asbroadcast indicator signals, from wireless devices. Broadcast receiverresponse air link resource 828 is used to carry interference controlsignals from receivers of the broadcast transmission request signals.Unicast transmission request air link resource 830 is used to carry peerto peer transmission request signals, while unicast receivertransmission request response air link resource 832 is used to carrytransmission request response signals in response to received peer topeer transmission request signals.

In some embodiments, a different structure is utilized for thebroadcast/unicast slot. For example, in another exemplary embodiment, astructure is used in which the broadcast transmission request resourceis joined with the unicast transmission request resource, e.g., in oneblock, and then the block is followed by a request response resourceblock.

FIG. 9 illustrates exemplary broadcast transmission request air linkresource 826 and exemplary broadcast receiver response air link resource828 in more detail. In this exemplary embodiment regarding broadcasting,more resources are allocated to response resources than to requestresources. Exemplary broadcast request resource 826 includes 12individual transmission request units, each associated with a differentbroadcast connection identifier. For example for this particular slot,broadcast transmission request transmission unit 902 is associated withbroadcast identifier 2, while broadcast transmission request unit 904 isassociated with broadcast identifier 5. Each position within thebroadcast transmission request air link resource 826 is associated witha priority, e.g., a different priority. In this example, transmissionunit 902 has higher priority than transmission unit 904. In someembodiments, from one broadcast/unicast slot to anotherbroadcast/unicast slot, the priority associated with a particularbroadcast device identifier changes, e.g., in accordance with a hoppingsequence which maps the broadcast identifier to different transmissionunit location within the broadcast transmission request resources.

Broadcast receiver response resource 828 includes sets of transmissionunits associated with each broadcast device identifier. For example,corresponding to broadcast device identifier 2, there are sixtransmission units (906, 908, 910, 912, 914, 916) allocated to carrycontrol interference signals. Similarly, corresponding to broadcastdevice identifier 5, there are six transmission units (918, 920, 922,924, 926, 928) allocated to carry control interference signals. Priorityis also associated with the different device identifiers within theresource 828.

FIG. 10 includes a drawing 1000 illustrating exemplary signaling in aregion of a peer to peer network in accordance with an exemplaryembodiment. In the example, of FIG. 10, assume that the broadcasttransmission request resource 826 and the broadcast receiver responseresource 828 described with respect to FIGS. 8 and 9 are utilized. Inthis example, WT A 1001 and WT A′ 1003 want to broadcast data in thesame air link data resource 822. Assume that WT A 1001 currently holdsbroadcast connection identifier 2 associated with broadcast requesttransmission unit 902 and broadcast receiver response transmission units(906, 908, 910, 912, 914, 916). Assume that WT A′ 1002 currently holdsbroadcast connection identifier 5 associated with broadcast requesttransmission unit 904 and broadcast receiver response transmission units(918, 920, 922, 924, 926, 928). Assume that for this slot the broadcastrequest associated with connection identifier 2 has higher priority thanthe broadcast request associated with connection identifier 5.

WT A 1001 generates broadcast transmission request signal 1002 which iscommunicated using transmission unit 902. The broadcast request signal1002 is received and recovered by WT B 1005, WT C 1007, and WT D 1009.WT A′ 1003 generates broadcast transmission request signal 1004 which isreceived and recovered by WT B 1005. WT C 1007 and WT D 1009 aresufficiently far enough away from WT A′ 1003 so that they do not detectthe broadcast request signal 1004 from WT A′ 1003 or detect it at such alow power level that it does not provide an interference problem withregard to receiving broadcast signals from WT A 1001.

WT B 1005 decides that it would like WT A′ 1003 to refrain frombroadcasting since from WT B's receiver perspective, concurrentbroadcast signals from WT A′ 1003 will unacceptably interfere with itsreception of broadcast signals from WT A 1001 which has higher priority.Therefore, WT B 1005 selects, e.g., randomly one of the responsetransmission units from the set of transmission units associated with WTA (906, 908, 910, 912, 914, 916). In this case WT B 1005 selects to usetransmission unit 910. WT B 1005 generates and transmits interferencecontrol signal 1006 using air link resource transmission unit 910.

WT A 1001 monitors for interference control signals on resourcesassociated with higher priority than its own priority level. WT A 1001does not detect any such interference control signals so it determinesthat it is ok to proceed with its intended broadcast.

WT A′ 1003 monitors for interference control signals on resourcesassociated with higher priority than its own priority level, and detectsinterference control signal 1006 on resource 910. The interferencecontrol signal 1006 is received by WT A′ 1003 at a level above athreshold. Therefore, WT A′ 1003 determines that it is not permitted tobroadcast data, and refrains from broadcasting a traffic signal in dataresource 822.

WT A 1001 transmits broadcast traffic signal 1008 in data resource 822which is successfully received and recovered by WT B 1005, WT C 1007 andWT D 1009.

FIG. 11 includes a drawing 1100 illustrating exemplary signaling in aregion of a peer to peer network in accordance with an exemplaryembodiment. In the example, of FIG. 11, assume that the broadcasttransmission request resource 826 and the broadcast receiver responseresource 828 described with respect to FIGS. 8 and 9 are utilized. Inthis example, WT A 1101 and WT A′ 1103 want to broadcast data in thesame air link data resource 822. Assume that WT A 1101 currently holdsbroadcast connection identifier 2 associated with broadcast requesttransmission unit 902 and broadcast receiver response transmission units(906, 908, 910, 912, 914, 916). Assume that WT A′ 1102 currently holdsbroadcast connection identifier 5 associated with broadcast requesttransmission unit 904 and broadcast receiver response transmission units(918, 920, 922, 924, 926, 928). Assume that for this slot the broadcastrequest associated with connection identifier 2 has higher priority thanthe broadcast request associated with connection identifier 5.

WT A 1101 generates broadcast transmission request signal 1102 which iscommunicated using transmission unit 902. The broadcast request signal1102 is received and recovered by WT B 1105, WT C 1107, and WT D 1109.WT A′ 1103 generates broadcast transmission request signal 1104 which isreceived and recovered by WT B 1105 and WT C 1107. WT D 1109 issufficiently far enough away from WT A′ 1103 so that it does not detectthe broadcast request signal 1104 from WT A′ 1103 or detects it at sucha low power level that it does not provide an interference problem withregard to receiving broadcast signals from WT A 1101.

WT B 1105 decides that it would like WT A′ 1103 to refrain frombroadcasting since from WT B's receiver perspective, concurrentbroadcast signals from WT A′ 1103 will unacceptably interfere with itsreception of broadcast signals from WT A 1101 which has higher priority.Therefore, WT B 1105 selects, e.g., randomly one of the responsetransmission units from the set of transmission units associated with WTA (906, 908, 910, 912, 914, 916). In this case WT B 1105 selects to usetransmission unit 910. WT B 1105 generates and transmits interferencecontrol signal 1106 using air link resource transmission unit 910.

WT C 1107 decides that it would like WT A′ 1103 to refrain frombroadcasting since from WT C's receiver perspective, concurrentbroadcast signals from WT A′ 1103 will unacceptably interfere with itsreception of broadcast signals from WT A 1101 which has higher priority.Therefore, WT C 1107 selects, e.g., randomly one of the responsetransmission units from the set of transmission units associated with WTA (906, 908, 910, 912, 914, 916). In this case WT C 1107 selects to usetransmission unit 914. WT C 1107 generates and transmits interferencecontrol signal 1108 using air link resource transmission unit 914.

WT A 1101 monitors for interference control signals on resourcesassociated with higher priority than its own priority level. WT A 1101does not detect any such interference control signals so it determinesthat it is ok to proceed with its intended broadcast.

WT A′ 1103 monitors for interference control signals on resourcesassociated with higher priority than its own priority level, and detectsinterference control signal 1106 on resource 910 and interferencecontrol signal 1108 on resource 914. WT A′ 1103 compares each of thereceived detected higher priority interference control signals to athreshold. In this example, at least one of the detected higher prioritycontrol signals exceeds a threshold. Therefore, WT A′ 1103 decides notto broadcast data, and refrains from broadcasting a traffic signal indata resource 822.

WT A 1101 transmits broadcast traffic signal 1110 in data resource 822which is successfully received and recovered by WT B 1105, WT C 1107 andWT D 1109.

WT A 1001, WT A′ 1003, WT B 1005, WT C 1007, WT D 1009 are, e.g.,wireless devices in accordance with one or more of FIGS. 3, 5, and/or 7and/or implementing one or more of the methods of FIGS. 2, 4 and/or 6.WT A 1101, WT A′ 1103, WT B 1105, WT C 1107, WT D 1109 are, e.g.,wireless devices in accordance with one or more of FIGS. 3, 5, and/or 7and/or implementing one or more of the methods of FIGS. 2, 4 and/or 6.

The techniques of various embodiments may be implemented using software,hardware and/or a combination of software and hardware. Variousembodiments are directed to apparatus, e.g., mobile nodes such as mobileaccess terminals, base stations including one or more attachment points,and/or communications systems. Various embodiments are also directed tomethods, e.g., method of controlling and/or operating mobile nodes, basestations and/or communications systems, e.g., hosts. Various embodimentsare also directed to machine, e.g., computer, readable medium, e.g.,ROM, RAM, CDs, hard discs, etc., which include machine readableinstructions for controlling a machine to implement one or more steps ofa method.

In various embodiments nodes described herein are implemented using oneor more modules to perform the steps corresponding to one or moremethods, for example, transmitting a broadcast indicator signalindicating an intent to broadcast data, monitoring for interferencecontrol signals following transmission of said broadcast indicatorsignal, making a decision whether or not to proceed with broadcastingdata based on the result of the monitoring, receiving from a seconddevice a first broadcast indicator signal having a first prioritycorresponding to said second device, said first broadcast indicatorsignal indicating an intent by the second device to broadcast data,receiving from a third device a second broadcast indicator signal havinga second priority corresponding to the third device, said secondbroadcast indicator signal indicating an intent by the third device tobroadcast data, making a decision whether or not to transmit aninterference control signal as a function of the relative priority ofthe first and second broadcast indicator signals, etc. Thus, in someembodiments various features are implemented using modules. Such modulesmay be implemented using software, hardware or a combination of softwareand hardware. Many of the above described methods or method steps can beimplemented using machine executable instructions, such as software,included in a machine readable medium such as a memory device, e.g.,RAM, floppy disk, etc. to control a machine, e.g., general purposecomputer with or without additional hardware, to implement all orportions of the above described methods, e.g., in one or more nodes.Accordingly, among other things, various embodiments are directed to amachine-readable medium including machine executable instructions forcausing a machine, e.g., processor and associated hardware, to performone or more of the steps of the above-described method(s). Someembodiments are directed to a device, e.g., communications device,including a processor configured to implement one, multiple or all ofthe steps of one or more methods of the invention.

Some embodiments are directed to a computer program product comprising acomputer-readable medium comprising code for causing a computer, ormultiple computers, to implement various functions, steps, acts and/oroperations, e.g. one or more steps described above. Depending on theembodiment, the computer program product can, and sometimes does,include different code for each step to be performed. Thus, the computerprogram product may, and sometimes does, include code for eachindividual step of a method, e.g., a method of controlling acommunications device or node. The code may be in the form of machine,e.g., computer, executable instructions stored on a computer-readablemedium such as a RAM (Random Access Memory), ROM (Read Only Memory) orother type of storage device. In addition to being directed to acomputer program product, some embodiments are directed to a processorconfigured to implement one or more of the various functions, steps,acts and/or operations of one or more methods described above.Accordingly, some embodiments are directed to a processor, e.g., CPU,configured to implement some or all of the steps of the methodsdescribed herein. The processor may be for use in, e.g., acommunications device or other device described in the presentapplication.

In some embodiments, the processor or processors, e.g., CPUs, of one ormore devices, e.g., communications devices such as wireless terminalsare configured to perform the steps of the methods described as being asbeing performed by the communications device. Accordingly, some but notall embodiments are directed to a device, e.g., communications device,with a processor which includes a module corresponding to each of thesteps of the various described methods performed by the device in whichthe processor is included. In some but not all embodiments a device,e.g., communications device, includes a module corresponding to each ofthe steps of the various described methods performed by the device inwhich the processor is included. The modules may be implemented usingsoftware and/or hardware.

While described in the context of an OFDM system, at least some of themethods and apparatus of various embodiments are applicable to a widerange of communications systems including many non-OFDM and/ornon-cellular systems.

Numerous additional variations on the methods and apparatus of thevarious embodiments described above will be apparent to those skilled inthe art in view of the above description. Such variations are to beconsidered within the scope. The methods and apparatus may be, and invarious embodiments are, used with CDMA, orthogonal frequency divisionmultiplexing (OFDM), and/or various other types of communicationstechniques which may be used to provide wireless communications linksbetween access nodes and mobile nodes. In some embodiments the accessnodes are implemented as base stations which establish communicationslinks with mobile nodes using OFDM and/or CDMA. In various embodimentsthe mobile nodes are implemented as notebook computers, personal dataassistants (PDAs), or other portable devices includingreceiver/transmitter circuits and logic and/or routines, forimplementing the methods.

1. A method of operating a peer to peer communications device,comprising: transmitting a broadcast indicator signal indicating anintent to broadcast data, said broadcast indicator signal having a firstpriority; monitoring for interference control signals which communicatea command or a request not to broadcast and which are transmitted inresponse to said broadcast indicator signal from other peer to peercommunications devices following transmission of said broadcastindicator signal; and prior to broadcasting data following transmissionof said broadcast indicator signal, making a decision whether or not toproceed with broadcasting data based on the result of said monitoring,wherein making a decision whether or not to proceed with broadcastingdata includes determining if an interference control signal having ahigher priority than said first priority level was received.
 2. Themethod of claim 1, wherein said broadcast indicator signal has a firstpriority level; wherein individual interference control signals detectedby said monitoring each have a priority level.
 3. The method of claim 2,wherein making a decision whether or not to proceed with broadcastingincludes, when an interference control signal having a higher prioritythan said first priority level: making an interference determinationbased on the power level of at least one received interference controlsignal having a higher priority than said first priority level.
 4. Themethod of claim 3, wherein making a decision whether or not to proceedwith broadcasting includes deciding not to broadcast when saidinterference determination determines that an interference level above athreshold level will be caused to the peer to peer communications devicewhich transmitted said interference control signal having a higherpriority than said first priority level if the broadcast proceeds. 5.The method of claim 3, further comprising: when said decision whether ornot to proceed with broadcasting data is a decision to broadcast data,broadcasting data in a traffic slot corresponding to said transmittedbroadcast indicator signal.
 6. The method of claim 2, furthercomprising: transmitting a second broadcast indicator signal indicatingan intent to broadcast data, said second broadcast indicator signalindicating a second priority level which is different from said firstpriority level.
 7. The method of claim 6, further comprising: prior totransmitting a second broadcast indicator signal, determining the secondpriority level based on a time varying function.
 8. The method of claim7, wherein said step of determining the second priority level is alsobased on an identifier corresponding to a communications deviceimplementing the broadcast transmission method.
 9. The method of claim2, wherein the broadcast indicator signal is transmitted on a singletone of an OFDM symbol.
 10. A peer to peer communications devicecomprising: a wireless transmitter for transmitting signals; a broadcastindicator signal generation module configured to generate a broadcastindicator signal indicating an intent to broadcast data, said broadcastindicator signal having a first priority; a broadcast indicator signalcontrol module configured to control the wireless transmitter tobroadcast said generated broadcast indicator signal; a responsemonitoring module configured to monitor for interference control signalswhich communicate a command or a request not to broadcast and which aretransmitted in response to said broadcast indicator signal from otherpeer to peer communications devices following transmission of saidbroadcast indicator signal; and a broadcast decision module configuredto make a decision whether or not to proceed with broadcasting databased on the result of said monitoring, said broadcast decision moduleis configured to make a decision whether or not to proceed withbroadcasting data as a function of a determination whether aninterference control signal having a higher priority than said firstpriority level was received.
 11. The peer to peer communications deviceof claim 10, wherein said broadcast indicator signal has a firstpriority level; and wherein individual interference control signalsdetected by said monitoring each have a priority level; the peer to peercommunications device further comprising: a priority comparison moduleconfigured to make said determination whether said interference controlsignal having a higher priority than said first priority level wasreceived.
 12. The peer to peer communications device of claim 11,further comprising: a power measurement module configured to measure thepower level of received interference control signals, and wherein saidbroadcast decision module is configured to make a decision whether ornot to proceed with broadcasting data based on the power level of atleast one received interference control signal having a higher prioritythan said first priority level when an interference control signalhaving a higher priority than said first priority level was detected bysaid response monitoring module.
 13. The peer to peer communicationsdevice of claim 12, further comprising: an interference determinationmodule configured to determine interference to other peer to peercommunications devices if the peer to peer communications device shouldproceed with a broadcast, and wherein said broadcast decision module isconfigured to make a decision not to broadcast when said interferencedetermination module determines that an interference level above athreshold level will be caused to the peer to peer communications devicewhich transmitted said interference control signal having a higherpriority than said first priority level if the broadcast proceeds. 14.The peer to peer communications device of claim 12, further comprising abroadcast traffic signaling control module configured to control saidwireless transmitter module to broadcast data in a traffic slotcorresponding to said transmitted broadcast indicator signal when saiddecision whether or not to proceed with broadcasting data is a decisionto broadcast data.
 15. The peer to peer communications device of claim14, further comprising: a broadcast indicator signal priority leveldetermination module configured to determine a priority level associatedwith a broadcast indicator signal to be transmitted by said peer to peercommunications device, and wherein said broadcast indicator signalpriority level determination module determines said priority level basedon a time varying function.
 16. The peer to peer communications deviceof claim 15, wherein said broadcast indicator signal priority leveldetermination module is configured to determine the priority level basedon an identifier corresponding to said wireless terminal intending totransmit the broadcast indicator signal.
 17. The peer to peercommunications device of claim 11, wherein the broadcast indicatorsignal is transmitted on a single tone of an OFDM symbol.
 18. A peer topeer communications device comprising: broadcast indicator signalgeneration means for generating a broadcast indicator signal indicatingan intent to broadcast data, said broadcast indicator signal having afirst priority; broadcast indicator signal control means for controllingwireless transmitter means to broadcast said generated broadcastindicator signal; response monitoring means for monitoring forinterference control signals which communicate a command or a requestnot to broadcast and which are transmitted in response to said broadcastindicator signal from other peer to peer communications devicesfollowing transmission of said broadcast indicator signal; and broadcastdecision means for making a decision whether or not to proceed withbroadcasting data based on the result of said monitoring, said broadcastdecision means making said decision whether or not to proceed withbroadcasting data as a function of a determination whether aninterference control signal having a higher priority than said firstpriority level was received.
 19. The peer to peer communications deviceof claim 18, wherein said broadcast indicator signal has a firstpriority level; and wherein individual interference control signalsdetected by said monitoring each have a priority level; and wherein thepeer to peer communications device further comprises: prioritycomparison means for making said determination whether said interferencecontrol signal having a higher priority than said first priority levelwas received.
 20. The peer to peer communications device of claim 19,further comprising: power measurement means for measuring the powerlevel of received interference control signals; and wherein saidbroadcast decision means makes a decision whether or not to proceed withbroadcasting data based on the power level of at least one receivedinterference control signal having a higher priority than said firstpriority level when an interference control signal having a higherpriority than said first priority level was detected by said responsemonitoring means.
 21. The peer to peer communications device of claim20, further comprising: interference determination means for determininginterference to other peer to peer communications devices if the peer topeer communications device should proceed with a broadcast, and whereinsaid broadcast decision means makes a decision not to broadcast whensaid interference determination means determines that an interferencelevel above a threshold level will be caused to the peer to peercommunications device which transmitted said interference control signalhaving a higher priority than said first priority level if the broadcastproceeds.
 22. The peer to peer communications device of claim 20,further comprising broadcast control means for controlling said wirelesstransmitter means to broadcast data in a traffic slot corresponding tosaid transmitted broadcast indicator signal when said decision whetheror not to proceed with broadcasting data is a decision to broadcastdata.
 23. A non-transitory computer program product, the computerprogram product comprising: a non-transitory computer readable mediumcomprising: code for causing a computer to control a peer to peercommunications device to transmit a broadcast indicator signalindicating an intent to broadcast data, said broadcast indicator signalhaving a first priority; code for causing a computer to control the peerto peer communications device to monitor for interference controlsignals which communicate a command or a request not to broadcast andwhich are transmitted in response to said broadcast indicator signalfrom other peer to peer communications devices following transmission ofsaid broadcast indicator signal; and code for causing a computer tocontrol the peer to peer communications device to make a decisionwhether or not to proceed with broadcasting data based on the result ofsaid monitoring, said code including code for causing a computer tocontrol the peer to peer communications device to determine if aninterference control signal having a higher priority than said firstpriority level was received.
 24. The method of claim 1, wherein saidother peer to peer communications devices includes at least one wirelessterminal.
 25. The method of claim 1, further comprising: prior totransmitting said broadcast indicator signal, determining a transmissionpriority level corresponding to said peer to peer communications device;and wherein transmitting a broadcast indicator signal includestransmitting a broadcast indicator signal having said determinedpriority level.
 26. The method of claim 1, wherein the priority level ofthe broadcast indicator signal is indicated by which one of a pluralityof OFDM tone symbols is used to transmit said broadcast indicatorsignal, different OFDM tone symbols in said plurality of OFDM tonesymbols corresponding to different priority levels.
 27. The method ofclaim 1, wherein the broadcast indicator signal is a single tone of anOFDM symbol and wherein the location of the single tone in a set of timeand frequency resources indicates the said first priority of thebroadcast indicator signal.
 28. The method of claim 1 wherein at leastsome of said other peer to peer communications devices are mobilewireless terminals which support peer to peer communications.
 29. Themethod of claim 1, wherein said peer to peer communications device andsaid other peer to peer communications devices are part of an ad hocnetwork.
 30. The method of claim 28, wherein transmissions are scheduledin said ad hoc network in a de-centralized manner, and wherein making adecision whether or not to proceed with broadcasting data is madewithout input from a centralized controller device.